1. Field of the Invention
The invention relates in general to a transformer and a backlight module thereof, and more particularly to a transformer for driving multi-lamps and a backlight module thereof.
2. Description of the Related Art
As the size of liquid crystal display (LCD) increases, the luminance provided by the backlight of the LCD must increase accordingly so as to main the display quality of an image. In order to increase the luminance of the backlight module, multiple lamps are used.
Referring to FIG. 1, a perspective of a conventional backlight module is shown. The conventional backlight module 10 comprises a driving circuit 110, a conventional transformer 120, and two lamps 130(1)˜130(2). The primary coil of the conventional transformer 120 is coupled to the driving circuit 110, and the secondary coil of the conventional transformer is coupled to the lamps 130(1)˜130(2).
However, as the currents I1 and I2 flowing through the lamps 130(1)˜130(2) are different from each other due to the characteristics of the lamp 130(1) and the lamp 130(2), the luminance generated by the lamp 130(1) is thus different from that generated by the lamp 130(2). As a result, the display quality of LCD is affected and deteriorates. Besides, when the currents I1 and I2 are unbalanced, the lifespan of the lamps will be shortened. Therefore, how to resolve the problem of unbalanced currents when driving multi-lamps has become an imminent issue to be resolved in the LCD industry.